it depends if it's half a degree centigrade, not so much. three, four, five, probably more. you point out that well, africa and maybe not so good. canada may be much better. it's a complicated issue. and size, which we do about it? can pretty much done the libertarian burial of letting market forces operate. if you have people that drive better cars, top-down government fiat controls will not feature. if the price of gas goes up, boom, people will -- if there's a market incentive for innovating better batteries, for example, like the nissan lever some of these. they are getting better. we have the least to go. not sure what the battery problem is. other than aliso 100-mile range is problematic for much of driving in los angeles without constant plug-in stations and that takes too long. but he didn't market forces will help get there.